What could be a fix for a modulus error in C

Question

I'd like to ask for help about this. I'm going to input two integers. All of the results are showing except for "modulus". Also the second and third "%d" is remaining as is. Here is the results when I run my program.

Enter First Number: 10
Enter Second Number: 20

10 + 20 = 30  
10 - 20 = -10  
10 * 20 = 200  
10 / 20 = 0  
10 % %d = %d

What could be the probable fix if this is my program:

#include <stdio.h>
#include <conio.h>
main()
{

  int num1, num2, sum=0, diff=0, prod=0, quot=0, mod=0;

  clrscr();

  printf("\nEnter First Number:");
  scanf("%d",&num1);
  printf("\nEnter Second Number:");
  scanf("%d",&num2);
  sum = num1 + num2;
  diff = num1 - num2;
  prod = num1 * num2;
  quot = num1 / num2;
  mod = num1 % num2;
  printf("%d + %d = %d", num1, num2, sum);
  printf("%d - %d = %d", num1, num2, diff);
  printf("%d * %d = %d", num1, num2, prod);
  printf("%d / %d = %d", num1, num2, quot);
  printf("%d % %d = %d", num1, num2, mod);
  getch();

}

`%` expects a format specifier after it. If you want to print a literal `%`, use `%%` in the format string. But this problem has been discussed countless times. Use the search. — The Paramagnetic Croissant, Nov 20 '15 at 10:45
Possible duplicate of [How to escape the % sign in C's printf?](http://stackoverflow.com/questions/1860159/how-to-escape-the-sign-in-cs-printf) — The Paramagnetic Croissant, Nov 20 '15 at 10:46
(and also of the [second Google hit](https://stackoverflow.com/questions/17774821/how-do-i-print-the-percent-sign-in-c)…) — The Paramagnetic Croissant, Nov 20 '15 at 10:47

score 2 · Accepted Answer · answered Nov 20 '15 at 10:46

The problem is here:

printf("%d % %d = %d", num1, num2, mod);
           ~~~~

When you use a % in the format string, printf will treat it as part of a conversion specification (like %d). If it's followed by something other than a valid specification, the results are undefined, so anything might happen.

If you need a literal % in the output, use %% in the format string:

printf("%d %% %d = %d", num1, num2, mod);

score 1 · Answer 2 · answered Nov 20 '15 at 10:45

1

The % character is used to denote a format string in printf.

Use %% to print the % character. Now, printf is expecting a format string, but there's only a space.

printf("%d %% %d = %d", num1, num2, mod);

answered Nov 20 '15 at 10:45

Arc676

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What could be a fix for a modulus error in C

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